Method of making bearings



Feb. 25, 1936. 5 SALZM'AN 2,031,982

METHOD OF MAKING BEARINGS Filed Sept. 28, 1931 INVENTOR.

Georg: jafifdrt ir (12 a,

A TTORNEYJ.

Patented Feb. 25, 1935 UNITED STATES:

PATENT orncs 2,031,982 METHOD OF MAKING'BEARINGS Application September28, 1931, Serial No. 565,557

reference to the quantity production of a semicylindrical orhalf-bearinghaving a bearingmetal 0r babbit lining and conforming tocertain necessary precision limits. The herein described method andapparatus is particularly applicable to bearings having a steel outerface, since one of the objects of my invention is to provide means forforming semi-cylindrical shapes which is especiallyadapted to act uponthe peculiar bending properties of steel.

A further object is to produce a bearing in which the bearing metal hasbeen subjected to a g compressive force or mechanical coldworking whichis productive of a refinement of the grain structure of the metal withcorresponding resultant increased strength and durability of thebearing. Objects and advantages additional to those above enumeratedshall become apparent during the following description.

. To the accomplishment of the foregoing and related ends, theinvention, then, consists of the method hereinafter fully described andparticularly pointed out in the claims.

The annexed drawing and the following description set forth in detailcertain means and one mode of carrying out the invention, such disclosedmeans and mode illustrating, however,

- but one of various ways in which the principle of the invention may beused. I

In said annexed drawing:-

Fig. 1 is an elevational view of a pair of-die I blocks constructed inconformity to the principles of my invention, showing the bearing blankin initial position; Figs. *2- and 3 illustrate further steps in thecompletion of the herein described process; Fig. 4 is a transversesectional view of a half-bearing in position on a shaft showing the flatspots which occur adjacent-the parting line to an exaggerated degree;Fig. 5 is another transverse sectional vview also showing. to anexaggerated degree the'manner in which the steel die stock tends to bendduring ordinary die as practice;

Directing attention particularly toFigs. 1, 2

and 3, a fiat piece of stock I is first placed in position upon theblank holders 2 and 3. This piece of bearing stock I is preferably of abi- 50 metallic composition, having the steel outer face a and the innerbearing metal or babbit portionb.

The upper or female die 4 has a semi-cylindrical face 5 from whichextends'a plunger 6. The plunger 6 carries the stop block 1 upon which65 bears the compression spring 8. It will thus be 6 Claims. (Cl.29149.5)

The present invention, relating as indicated to the manufacture ofbearings, has more particular lows:-The forming core it], which has adie sur- 10.

face corresponding to a segment of the inner surface of thehalf-bearing, is carried upon the reciprocal shaft II. The shaft is inturn springlcaded by means of the stop washer I2 and compression spring3. The compressicnspring I3 15 is of a strength sufficient to overcomethe arcuate bending resistance of the bearing blank, I. As shown in Fig.2, the bearing blank I has been completely conformed to the innersurface 5 of the female die, and the compression spring 13 has not yetbegun to act. In Fig. 3, however, upon the exertion of increasedpressure upon the die block 9 the resistance of the spring I3 isovercome and the ironing pad M and upsetting punch l5 are forced with asudden impact against the bearing blank. The ironing pad l4 alsoservesthe function in that it prevents a thickening of the bearing alongthose portions with which it contacts, and forces the metal toward thecentral part of the bearing,- with the result that there is accomplisheda uniform upsetting action which is productive of uniform wallthickness. The force with which the punch I5 is driven against theparting line edges i6 and ll of the bearing blank I is sufiicient toimpart an upsetting action to the 35 metallic structure of the blank.The die or forming core I0, it should be noted, does not'at any timeseat upon the ironing pad or upsetting punch I 4 and [5 respectively,but is always un-' der spring pressure permitting the metal of the 40hearing blank to move comparatively freely when the upsetting punch l5strikes home. As shown in Fig. 3, there is always some clearance betweenthe forming core I ii and ironing pad ll along the line 25.

' The purpose of this last-described action of the .forming core ID inconjunction with the ironing pad I4 is to permit the force of theupsetting blow to be transmitted throughout the arcuate section of thebearing blank.

For the purposes of further illustration of the theory of my invention Ihave shown in Fig. 4 a

bearing blank I which has merely been subjected to thecoin-pressingact'ion of two semi-cylindrical dies. It will be noted thatthere occur the 5 Z4 ment in the bearing metal portion.

be further noted that this final mechanical work'- 'ing or refinement ofthe grain structure is pro- 10 line of the bearing, and of sufiicientmagnitude to rearrange the grain structure of the materialofthe-bearing.

In order to still further illustrate the func tional features of mymethod and apparatus, 15 there has ,been shown in Fig. 5 the manner inwhich the die stock, especially when of steel constituency, tends tobulge at its center portion. This bulge is indicated to an exaggerateddegree at the point'24.. The presence of the spring 20 loadedretractable plunger 6 therefore is for the purpose of eliminating thetendency of the die stock to bend into a radius less than that of the xsemi-cylindrical die. I, y Y

, t should also benoted that the presence of the f ing'co're or die I!)maybe dispensed with p when the upsetting pressure is, exerted along theparting line of the bearing die stock. The forming core Ill, afterperforming its function of con--' forming the flat blank to thesemi-cylindrical die 30 surface 5, effects no, furthermechanical'deformation upon the die stock and during the upsettingstroke serves merely as a means for properly re? taining thesemijcylindrical blank in-place,

- My method and apparatus perform the further 5 function in that thereisimparted a refining or densifying action upon the bearing metal b. 7When the bi-metallic blank is first arcuated .as shown in Fig.2, thereoccurs a slight extrusion of the hobbit, due to the fact that the inners ace 40 of the bearingblank l is subjected to the gr ater deformation,When the upsetting punch strikes 5 home,as shown inFig. 3, there isexerted upon the babbit metal portion b a secondary mechanicaldeformation which produces a grain "refine- It should duced by stressacting in a tangential direction,

which hasa tendency therefore to improve the '50 properties of thebearing metal in that particular.direction in which the maximum stresseswill be exerted upon it when in use.

, It will thus be seen that my invention provides a'method and means f reconomically and rapid I 55 1y producing .sem'i-cyli drical bearingswhich will 1 not'only conform to the requirements of precl; sionpractice, but also possess improved qualities of durability. a f vOthenforms may be employed embodying the features of my inventioninstead of the one here explained, change being made in the form orcons'truction, provided the elements 'stated by any of I H, I I V J V Lbearing,- and then applying a compressive force the following claims orthe equivalent of such stated elements be employed, whether producedby-my preferred method or by others embodying steps equivalent to thosestatedin the following claims.

l I therefore particularly point out and distinctly claim as myinvention:---

1. In the manufacture Y of semi-cylindrical bearings and the like, themethod of conforming the bearing to a radius equal to that of the com-10 pleted article and then applying a tangentially directed forceagainst the parting line of.,the bearing suflicient to mechanicallydeform andrearrange the grain structure ofthe bearing material.

2. In the -manufacture of semi-cylindrical bearingsand the like, themethod of arcuating the central portion of a flat blank to a radiusequal to that of the completed bearing and then applying a compressiveforce against the end facesof, said blanlg whereby the blank issubjected to mechanical deformation and the grain structureof itsmaterial rearranged. 4

3. In the .manufacture of semi-cy ndrical bearings andthe like, themethod of arcuating the central portion "of a hat blank to a radiusequal to that of the completed bearing, and then applying a compressiveforce against the parting line of the bearing, whereby the blank issubjected to me hanical deformation and the grain structure of tsmaterial rearranged.

4. In the manufacture of semi-cylindrical "bearings and the like;'themethod of arcuating' the central perigicn' of a flat blank to a radiusequal to that of the completed bearing, and then applying a compressiveforce against the parting line of the bearing, while saidcentral portionis held under forming pressure, whereby the' blank is subjected tomechanical deformation and the grain structure of its materialrearranged.

5. In the nufacture of semi-cylindrical bearings and. the like, themethod of arcuating the central portion of a flat bla k 'to a radiusequal to that of the completed bea ng, and then subjecting the end facesto a sudden impact tangentially directed against the parting line of thebearing, whereby the blank is subjected .to mechanical deformation andthe grain structure fofits material rearranged. 6.'-I-n the manufactureof semi-cylindrical bearings and the like, the method of retaining thecenter portion of a fiat blank against'an arcuate male die surfaceduring the operation of arcuate bending of said blank, conforming saidblank to a radius equal to that of the completed againstvthe partingline of the bearing, whereby -the blank is subjected to mechanicaldeformation and thegrain structureof its material rear ranged. 1

v GEORGE S. SALZMAN.

